Rock drill



A. H. SKAER ROCK DRILL 0 Filed my 12, 1925 Jan. 29, 1929.

Hu an.

Patented Jan. 29, 1929.

mrso STATES PATENT OFFICE.

ARTHUR H. SKAER, OF DENVER, COLORADO, ASSTGNOR, BY MESNE ASSIGNMENTS, TO

THE G.ARDNERDENVER COMPANY, OF

DELAWARE.

QUINCY, ILLTNOIS, A CORPORATION OF ROCK DRILL.

Application filed May 12, 1923. Serial No. 638,554.

The present invention relates to rock drilling machines of the type inwhich an extensible fluid-actuated feeding member is employed.

The object is to provide a simple and novel structure convenientlyoperable by the drill runner for controlling the supply of motive fluidto and its exhaust from the feeding member.

The preferred embodiment is illustrated in the accompanying drawings,wherein Figure 1 is a View partially in section and partially inelevation of a rock drill equipped with the structure.

Figures 2 and 3 are sectional views respectively on the lines 22 and 33of Figure 1, Figure 2 showing the valve turned 90 degrees from theposition shown in Figs. 1 and 3.

In the embodiment disclosed a drilling motor of well-known type isemployed, comprising a barrel 3, in which a reciprocatory piston hammer4 is actuated by air or other expansible motive fluid and operates on atappet 5, against which a drill steel 6 abuts. The barrel is mounted atits rear end on a head block 7, containing a chamber 8 for a taperedthrottle valve 9 that controls the supply of motive fluid both to thedrilling motor and the extensible feed member, as clearly shown in Fiure 1. A coupling 10 at one end of the chamber serves as means by whichan air supply hose can be connected to the machine, and the taper valve9 has an internal supply chamber 11 open at one end, and having alateral port 12 that is movable into and out of communication with asupply passageway 13 delivering to the barrel 3 and serving to supplymotive fluid for actuating the hammer piston 4.

The extensible feed member consists of a cylinder 14, suitably securedto the head block 7 and as usual containing a piston carrying a plungerrod 15 that terminates in a spur 16. A passageway 17, leading from oneside of the valve seat 8, opens into the front end of the cylinder 14 inadvance of the piston and obviously when motive fluid is admitted tosaid passageway, will cause the cylinder 14 and the drilling motor tomove upwardly on the plunger rod 15 if the spur 16 is placed upon asuitable base or support. The means for controlling the supply of fluidto the passageway 17 and its exhaust constitutes the subject-matter ofthe present invention.

The taper valve 9 has a shank portion 18 projecting from the head blockor valve seat, and on this shank is fixed a handle crank 19. The shankis furthermore provided with a longitudinal bore, constituting a valvechamber 20, having its inner end opening into the supply chamber 11 ofthe taper valve 9 and said open communication constituting a supply portto the chamber of the same. A lateral exhaust port 21 opens from thechamber 20 through the shank 18 to atmosphere. Forming an extension ofthe supply and eX- haust passageway 17 is a groove 22 formedlongitudinally in the exterior of the valve 9, this groove terminatingin divergent ports 23 and 24, opening at different points in the chamber20. A reciprocatory plunger valve is mounted in the chamber 20 andincludes a shank 25 having a terminal head 26 and provided with anannular groove 27. This shank carries at its outer end a thumb-piece 28that is located at the inner end of the crank handle 19, and is sopositioned that a drill runner holding the crank handle 19 will have thethumb piece 28 in a position to be pressed by his thumb.

When the throttle Valve 9 is open, or in the position shown in Figure 2,the groove 22 and ports 23 and 24 are in communication with thepassageway 17 leading to the extensible feed member. It will also benoted particularly by reference to Figure 3 that when the plunger valveis in its outermost position the port 23 will be in communica tion withthe supply chamber 11 through the inner end or supply port of the valvedesignated 20, and consequently motive fluid will flow freely from thechamber 11 through the port 23 and passageway 17 to the feed member,providing the necessary operative pressure therein. If the operatorpresses upon the thumb-piece 28 to move it to its innermost position, asshown in Figure 2, then the supply of motive fluid to the passageway 17is obviously cut oil, but exhaust can take place through the port 24,groove 27 and port 21. The valve may also be moved to an intermediateposition, in which case both ports 23 and 24 will be closed, cutting offcommunication between the passageway 17 and the supply chamber 11 andalso the exhaust port 21.

This is a valuable feature inasmuch as it permits the operator to cutdown the feed pres sure by shutting off the supply and utilizing theexpansion of the fluid held in the feed member. It will be obvious thatthe drill runner can thus conveniently control the feeding action as hemay find most desirable under different conditions and this control canbe obtained by using the thumb of the hand which grasps the throttlevalve, itbeing obvious that the pressure of the fluid against the head26 will move the plunger valve outwardly when released.

From the foregoing, it is thought that the construction, operation andmany advantages of the herein described invention will be apparent tothose skilled in the art, with out further description, and it will beunderstood that various changes in the size, shape, proportion and minordetails of construction, may be resorted to without departing from thespirit or sacrificing any of the advantages of the invention. V

Having thus fully described my invention, What I claim as new, anddesire to secure by Letters Patent, is

1. The combination with a fluid actuated drilling motor and a fluidactuated feeding member therefor, of a throttle valve controlling thesupply of motive fluid to the drilling motor and feeding member, saidvalve haw ing a valve chamber with a fluid supply port opening therento, a del very port that communicates with the feeding member and anexhaust port opening through the throttle valve to atmosphere, and avalve mounted in the valve chamber of the throttle valve and movable toa position to afford communication between the supply port and deliveryport and to another position to afford communication between thedelivery port and the exhaust port.

2. The combination with a fluid actuated drilling motor and a fluidactuated feeding member therefor, of a throttle valve control ling thesupply of motive fluid to the drilling motor and feeding member, saidthrottle valve having an exposed end provided with an actuating handleand being furthermore provided with an internal valve chamber having afluid supply port opening thereinto, a delivery port that communicateswith the feeding member and an exhaust port opening through the exposedend of the throttle tudinal valve chamber opening into the sup plychamber, said valve chamber having spaced ports that communicate withthe feeding member when the valve is in a predetermined position andalso having an exhaust port opening to atmosphere through the exposedend of the throttle valve, and a reciprocatory plunger valve in thevalve chamber having a head that is movable to close either or both thespacedports or afford communication between one of said spaced ports andthe supply chamber andbetween the others and the exhaust port. I

In testimony whereof, I aflix my signature.

ARTHUR H. SKAER.

